By Jeff Zeleny, Sarah Westwood and Pamela Brown, CNN

(CNN) -- President Donald Trump is deepening his investment in the midterm elections, stepping up his travel across the country to raise money and rally Republicans in hopes of overcoming the tide of history by retaining control of Congress in the fall.

Nearly every president in modern history has lost congressional seats during their first midterm election, a fact that Trump has told advisers he doesn't believe necessarily applies to him.

The top priority for the White House is holding the Republican majority in the Senate, which is critical for preserving the agenda and making judicial appointments for the remainder of the President's first term.

Trump is heading here to Texas on Thursday to do what party leaders say is the best way he can help: Raising money. He is set to mingle with GOP donors behind closed doors at a Houston luncheon, where the contributions range from $5,000 per person to $100,000 per couple, which allows a picture with the President.

"Your vote in 2018 is every bit as important as your vote in 2016," Trump told a gathering of social conservatives last week. He paused before telling the crowd, "I'm not sure I really believe that. I don't know who the hell wrote that line," he said to applause.

Yet the laughter underscores a brutal truth inside the White House: the President is already prioritizing his own re-election bid more than two years away.

He is also set to hold a fundraising dinner on Thursday evening in Dallas to benefit his campaign and the Republican National Committee. Those events have raised the eyebrows of some party loyalists, who believe Republicans should focus on 2018 before his re-election in 2020.

Trump filed his re-election papers at the time of his inauguration, more than two years earlier than his two recent predecessors. President Barack Obama didn't file for re-election until April 2011 and President George W. Bush until May 2003 -- both of which were after the first midterm elections of their presidency.

Red state pressure

Still, aides say, Trump is increasingly focusing on the November elections. He is set to increase his travel -- with a goal of at least one trip a week -- initially focusing on red states where Democratic senators are vulnerable.

In the coming weeks, aides say, he is poised to return to North Dakota, Missouri, Indiana and West Virginia -- all states he has already visited. He's also eyeing states where Republicans candidates face tough Democratic opponents.

That was the case in Tennessee, where the President traveled Tuesday to campaign on behalf of Rep. Marsha Blackburn, who is running to fill the seat Sen. Bob Corker will vacate. Blackburn faces former Democratic Gov. Phil Bredesen, who is considered a strong candidate even in the deep red state.

"When you win the presidency, for some reason you always end up losing the House," Trump told supporters in Nashville. "I think what happens is you get complacent."

It's that complacency that Trump believes he can change, urging his supporters to turn out in November even if the aren't regular midterm election voters.

The President, who receives regular briefings on Senate and House races, is expected to increase his travel to two or three times a week heading into the late fall, a White House official said. Trump had shown an interest in traveling as much as five times a week in the run-up to the fall, but aides suggested a lighter and more targeted schedule.

Yet Trump -- and perhaps his aides -- are hardly steeped in details of some key races, a point made clear Wednesday night when he endorsed a New York congressman on Twitter and praised him for supporting the Republican tax cut bill last year. But Rep. Dan Donovan, who represents Staten Island and Brooklyn, actually voted against the President's signature legislation.

Since the start of 2018, Trump has had a weekly meeting focused on the midterms, usually on Fridays. Through charts, graphs and recent polls, advisers walk him through the terrain of critical Senate and House contests. He often asks aides how he fared in the respective districts or states.

"The Trump map remains the most important map," a Republican close to the White House said.

One key Republican fear has been allayed: deep divisions inside the party. Trump has largely followed the direction of party leaders, declining to follow the counsel from some outside advisers by challenging incumbents.

Pence's role

The broad outlines of the White House's midterm strategy were developed in January when Trump, Vice President Mike Pence and top GOP congressional leaders convened for a weekend at Camp David, aides said. It has been updated over regular dinners at the White House, where Trump often tells his guests that he believes his presidency could break the path of the party in power losing seats.

During that initial summit, Senate Majority Leader Mitch McConnell laid out the "biggest asks" needed to protect the Senate majority, and House Majority Leader Kevin McCarthy did the same for the lower chamber.

Pence and Trump will take on different roles during the midterms, with Pence focusing more on fundraising and smaller campaign events, a vice presidential aide said, even while trying to protect the House majority from what is expected to be a wave of Democratic enthusiasm in November.

"You're not going to see as much of him doing these big events," the aide said of Pence, who will instead help fundraise for a variety of Republican groups, including the Republican National Committee, the National Republican Congressional Committee and state parties.

Although preparations for the possible Singapore summit with Kim Jong Un and other foreign policy issues have "sidetracked" Pence recently from his political work, the aide said Pence will ramp up his time on the campaign trail in the weeks ahead.

Pence will also help raise money for Great America Committee, his political action committee, and distribute checks from that PAC to House Republican candidates. Corey Lewandowski, Trump's former campaign manager, recently joined that effort.

To ward against complacency among his base voters, Trump has increashe iingly made immigration a focus of the fall Republican message, falsely accusing Democrats of defending violent gangs like MS-13 by declining to support his border wall in Congress. Pence is likely to ramp up messaging on immigration and border security as well during upcoming political appearances, the vice presidential aide said.

Stacked deck

For all of the planning inside the White House and at the Republican National Committee, the deck is still stacked against Republicans this year.

One concern among White House aides and Republican congressional leaders is complacency among House GOP incumbents. The fear among many Republicans is that lawmakers in conservative districts who have never faced tough re-election battles, such as members who rode in on the Tea Party wave of 2010, don't fully understand just how tough the political landscape has become heading into November.

Not only does history suggest the party of the President could lose dozens of seats in the first midterm election of his presidency, but Republicans must confront a Democratic base whose opposition to Trump has fed the expectation of a coming "blue wave."

Trump made clear in Nashville on Tuesday night that his supporters must get fired up.

"This election is a very important one," Trump told his followers. "So you have to get out."